In this 5-year prospective randomized clinical trial (RCT), the effectiveness of two interventions approaches will be evaluated in their ability to reduce HIV drug and sex-related risk behaviors among IDUs in Ukraine. Using an intent to treat design, we propose to compare a manually-driven HIV testing and counseling intervention, the Counseling and Education (C & E) model developed during NIDA's Cooperative Agreement (Coyle 1993), with the C & E plus a network-focused intervention that is also manually-driven developed by Latkin (2003) who has agreed to be a consultant. We have assessed both interventions in Ukraine and found them to be effective in reducing risks associated with HIV. They have not, however, been compared to one another and we have not employed a RCT design in our past work. We are proposing this test because: 1. in our recently completed 5-year Ukraine study the C & E intervention alone was as effective as the C & E plus a more intensive individual model; 2. this study also found that those who learned they were HIV infected when tested at baseline, regardless of intervention assignment, reduced their sex risks more than HIV negatives and those who already knew they were positive, underscoring the ethical necessity for testing and counseling and the merits of the C & E; 3. nevertheless, network interventions have the advantage over individually-focused interventions, including the C & E, in their potential to affect a much wider group of injectors, specifically, those who interact with indexes. We will also assess secondary diffusion by 'first wave' network members recruiting 'second wave' network members, something that heretofore has not been done. Assessing two steps out in the network will allow us to examine diffusion, overlap, contamination, and index and network characteristics that predict diffusion and resistance to behavioral change. Both interventions are theoretically- based, manually-driven, translated into Russian and both have been implemented successfully in Ukraine. In addition, because of the high HIV prevalence among IDUs in the sites selected (ranging from 20% to 65% in our past studies), we have included partner disclosure as part of both interventions and brought in Dr. Seth Kalichman, an expert in this area, as a consultant. In collaboration with our Ukraine Co-I, Sergiy Dvoryak, M.D., Ph.D., we will recruit 2250 IDUs, 750 each from Odessa, Makeevka/Donetsk and Nikolayev, who will receive either the network-focused network intervention plus C & E or C & E alone. Participants will be recruited through street outreach, interviewed, intervened with and followed at six and 12 months. In addition to the ACASI, biological samples will be taken to be assessed for HIV and the presence of drug metabolites.